US 12,435,167 B2
Processes for producing polyolefins and impact copolymers with broad molecular weight distribution and high stiffness
Xiaodan Zhang, Houston, TX (US); Christopher G. Bauch, Seabrook, TX (US); Lubin Luo, Houston, TX (US); Jeffrey L. Brinen, League City, TX (US); George J. Pehlert, Houston, TX (US); Todd S. Edwards, League City, TX (US); and Sung A. Kim, Houston, TX (US)
Assigned to EXXONMOBIL CHEMICAL PATENTS INC., Baytown, TX (US)
Appl. No. 17/640,172
Filed by EXXONMOBIL CHEMICAL PATENTS INC., Baytown, TX (US)
PCT Filed Aug. 14, 2020, PCT No. PCT/US2020/046301
§ 371(c)(1), (2) Date Mar. 3, 2022,
PCT Pub. No. WO2021/045889, PCT Pub. Date Mar. 11, 2021.
Claims priority of provisional application 62/896,064, filed on Sep. 5, 2019.
Prior Publication US 2022/0332864 A1, Oct. 20, 2022
Int. Cl. C08F 10/06 (2006.01); C08F 210/06 (2006.01)
CPC C08F 210/06 (2013.01) 20 Claims
OG exemplary drawing
 
1. A method for producing polyolefin comprising the steps of:
polymerizing α-olefin monomers with a catalyst and hydrogen in a slurry to produce a low molecular weight polyolefin having a weight average molecular weight between 20 kDa to 200 kDa;
venting hydrogen from the low molecular weight polyolefin; and
polymerizing the low molecular weight polyolefin and α-olefin monomers in the presence of catalyst having a mole ratio of hydrogen to α-olefin monomers of between 0 to 0.01 to produce polyolefin having a molecular weight distribution of between 4.0 and 20.0 and a flexural modulus between 1500 mPa and 2500 mPa.